Ouvrez une page html dans le navigateur par défaut avec VBA?

Vous pouvez utiliser la fonction Windows API ShellExecute de le faire:

Option Explicit

Private Declare Function ShellExecute _
  Lib "shell32.dll" Alias "ShellExecuteA" ( _
  ByVal hWnd As Long, _
  ByVal Operation As String, _
  ByVal Filename As String, _
  Optional ByVal Parameters As String, _
  Optional ByVal Directory As String, _
  Optional ByVal WindowStyle As Long = vbMinimizedFocus _
  ) As Long

Public Sub OpenUrl()

    Dim lSuccess As Long
    lSuccess = ShellExecute(0, "Open", "www.google.com")

End Sub

Juste un petite remarque concernant la sécurité: Si l'URL provient de la saisie de l'utilisateur assurez-vous de respecter strictement valider cette entrée comme ShellExecute à l'exécution de toute commande avec les autorisations de l'utilisateur, qui est aussi un format c: serait exécuté si l'utilisateur est un administrateur.

Si vous voulez une solution plus robuste avec ShellExecute qui permettra d'ouvrir n'IMPORTE quel fichier, dossier ou l'URL à l'aide de l'OS par défaut, le programme associé à le faire, voici une fonction de prise de http://access.mvps.org/access/api/api0018.htm:

'************ Code Start **********
' This code was originally written by Dev Ashish.
' It is not to be altered or distributed,
' except as part of an application.
' You are free to use it in any application,
' provided the copyright notice is left unchanged.
'
' Code Courtesy of
' Dev Ashish
'
Private Declare Function apiShellExecute Lib "shell32.dll" _
Alias "ShellExecuteA" _
(ByVal hwnd As Long, _
ByVal lpOperation As String, _
ByVal lpFile As String, _
ByVal lpParameters As String, _
ByVal lpDirectory As String, _
ByVal nShowCmd As Long) _
As Long
'***App Window Constants***
Public Const WIN_NORMAL = 1         'Open Normal
Public Const WIN_MAX = 3            'Open Maximized
Public Const WIN_MIN = 2            'Open Minimized
'***Error Codes***
Private Const ERROR_SUCCESS = 32&
Private Const ERROR_NO_ASSOC = 31&
Private Const ERROR_OUT_OF_MEM = 0&
Private Const ERROR_FILE_NOT_FOUND = 2&
Private Const ERROR_PATH_NOT_FOUND = 3&
Private Const ERROR_BAD_FORMAT = 11&
'***************Usage Examples***********************
'Open a folder:     ?fHandleFile("C:\TEMP\",WIN_NORMAL)
'Call Email app:    ?fHandleFile("mailto:[email protected]",WIN_NORMAL)
'Open URL:          ?fHandleFile("http://home.att.net/~dashish", WIN_NORMAL)
'Handle Unknown extensions (call Open With Dialog):
'                   ?fHandleFile("C:\TEMP\TestThis",Win_Normal)
'Start Access instance:
'                   ?fHandleFile("I:\mdbs\CodeNStuff.mdb", Win_NORMAL)
'****************************************************
Function fHandleFile(stFile As String, lShowHow As Long)
Dim lRet As Long, varTaskID As Variant
Dim stRet As String
'First try ShellExecute
lRet = apiShellExecute(hWndAccessApp, vbNullString, _
stFile, vbNullString, vbNullString, lShowHow)
If lRet > ERROR_SUCCESS Then
stRet = vbNullString
lRet = -1
Else
Select Case lRet
Case ERROR_NO_ASSOC:
'Try the OpenWith dialog
varTaskID = Shell("rundll32.exe shell32.dll,OpenAs_RunDLL " _
& stFile, WIN_NORMAL)
lRet = (varTaskID <> 0)
Case ERROR_OUT_OF_MEM:
stRet = "Error: Out of Memory/Resources. Couldn't Execute!"
Case ERROR_FILE_NOT_FOUND:
stRet = "Error: File not found.  Couldn't Execute!"
Case ERROR_PATH_NOT_FOUND:
stRet = "Error: Path not found. Couldn't Execute!"
Case ERROR_BAD_FORMAT:
stRet = "Error:  Bad File Format. Couldn't Execute!"
Case Else:
End Select
End If
fHandleFile = lRet & _
IIf(stRet = "", vbNullString, ", " & stRet)
End Function
'************ Code End **********

Il suffit de mettre ceci dans un module séparé et appels fHandleFile() avec les bons paramètres.